package com.yfw.maple_leaf_store.filter;

import com.alibaba.fastjson.JSON;

import com.yfw.maple_leaf_store.common.BaseContext;
import com.yfw.maple_leaf_store.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @author: yfw
 * @date: 2022/6/5 17:50
 * com.yfw.reggie.filter
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符比较，而string比较不支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();// /backend/index.html

        log.info("拦截到请求：{}", requestURI);
        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/MapleLeafStore/**",//前端页面交给前端SessionStore做前端页面拦截
                "/common/**",
                "/user/login",
                "/user/register",
                "/user/logout",
                "/cate/list",//查询所有分类
                "/goods/list",//用户可以查看商品，但是不能看购物车信息、个人中心
//                "/goods/**",
//                "/shopping/**",
//                "/cate/**",
//                "/user/**",
//                "/cate/**",
//                "/order/**",
//                "/addressBook/**"



        };
        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);

            filterChain.doFilter(request, response);
            return;
        }

        //4-2、判断移动端用户登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("user") != null) {
            log.info("用户已登录，用户id为：{}", request.getSession().getAttribute("user"));
            //用户登录成功后将session共享变量放入线程共享变量中
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request, response);
            return;
        }

        log.info("用户未登录");
        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应java对象转JSON数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));//服务器的响应信息会被前端的响应拦截器拦截，进行页面拦截
        return;

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
